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I've been using Faraday's law to find the EMF in a coil of wire in a changing magnetic field.

EMF = -N (change in mag flux/change in time) for N loops

I'm finding that the EMF is always positive regardless of whether the change in flux is positive or negative. I'm wondering at what point we choose to ignore the negative sign and why?

*What I've been considering...*

- I was thinking it could be a vector/scalar issue. But scalars can be negative.
- I think that the sign of the change in flux is important (Lenz's law etc).
- I understand that conservation of energy requires the induced EMF to oppose the change in flux. So the negative sign is important in the law.
- So is the sign of the EMF not important for some reason?

Thanks for your help.